Technical Field
Embodiments of this disclosure relate to a method of manufacturing an electromechanical transducer having a piezoelectric film, an electromechanical transducer, a droplet discharge head having the electromechanical transducer, and a droplet discharge apparatus and an image forming apparatus having the droplet discharge head.
Description of the Related Art
An image forming apparatus or a three-dimensional shaping apparatus such as a printer, a fax machine, and a copier is known that includes a droplet discharge head to discharge droplets. The droplet discharge head includes nozzles to discharge droplets, a liquid chamber (also referred to as ink channel, pressure liquid chamber, compression chamber, pressure chamber, discharge chamber, or individual liquid chamber) which the nozzles communicate with, and a heat generator to generate pressure in liquid in the liquid chamber. The liquid in the liquid chamber is pressurized by an energy generator, so that the droplets can be discharged from the nozzles communicating with the liquid chamber.
As systems for the droplet discharge head, for example, a piezoelectric system using an electromechanical transducer having a piezoelectric film, a heating system using an electrothermal transducer such as a heater, and an electrostatic system using a diaphragm forming a wall surface of a compression chamber and an electrode facing the vibration plate are known.
As droplet discharge heads using the piezoelectric system, for example, two types of droplet discharge heads are known: one using an electromechanical transducer vibrating in a vertical vibration mode and the other using an electromechanical transducer vibrating in a flexural vibration mode. The vertical vibration mode is a vibration mode in which a piezoelectric film is deformed to extend and contract in a thickness direction (a direction of a center axis) and the flexural vibration mode is a vibration mode in which an entire piezoelectric film is deformed to bend. For electromechanical transducers that vibrate in the vibration mode, fatigue phenomenon is known that the deformation amount (surface displacement amount) of the piezoelectric film applied with a drive voltage decreases over time.